The Kärcher Flat Hose 10m Extra Strong is a drain hose which you can connect to a submersible pump. With a 42m diameter, a lot of water goes through the hose. That's useful, because you can drain water quickly in case of a flood, for example. If there's no water in the 10m hose, it stays flat. That way, you can easily roll it up and it doesn't take up a lot of space. The Kärcher Flat Hose 10m Extra Strong includes a hose clamp with a wing screw. With this, you can easily connect the hose to your submersible pump without extra tools.